Re: コマ問

Gzip 1.3.11 (2007-02-05)で仕様が変更されています。

Major changes in Gzip 1.3.11 (2007-02-05)

* As per the GNU coding standards, the behavior of gzip and its
companion executables no longer depend on the name used to invoke them.
For example, 'gzip' and 'gunzip' are no longer hard links;
instead, 'gunzip' is now a small program that invokes 'gzip -d'.

* zdiff now checks for subsidiary gzip failures, and works around
bugs in IRIX 6 sh, Tru64 4.0F ksh, and Solaris 8 bash.

現行のバージョン（rhel8互換OS）に付属するgzipでも '-k' が使用可能です。

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$ gzip -h
Usage: gzip [OPTION]... [FILE]...
Compress or uncompress FILEs (by default, compress FILES in-place).

Mandatory arguments to long options are mandatory for short options too.

-c, --stdout write on standard output, keep original files unchanged
-d, --decompress decompress
-f, --force force overwrite of output file and compress links
-h, --help give this help
-k, --keep keep (don't delete) input files
-l, --list list compressed file contents
-L, --license display software license
-n, --no-name do not save or restore the original name and timestamp
-N, --name save or restore the original name and timestamp
-q, --quiet suppress all warnings
-r, --recursive operate recursively on directories
--rsyncable make rsync-friendly archive
-S, --suffix=SUF use suffix SUF on compressed files
--synchronous synchronous output (safer if system crashes, but slower)
-t, --test test compressed file integrity
-v, --verbose verbose mode
-V, --version display version number
-1, --fast compress faster
-9, --best compress better

With no FILE, or when FILE is -, read standard input.

Report bugs to <bug-gzip@gnu.org>;.
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